CN106877757A - DC motor speed-regulating control system and its speed detection method - Google Patents
DC motor speed-regulating control system and its speed detection method Download PDFInfo
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- CN106877757A CN106877757A CN201710152263.8A CN201710152263A CN106877757A CN 106877757 A CN106877757 A CN 106877757A CN 201710152263 A CN201710152263 A CN 201710152263A CN 106877757 A CN106877757 A CN 106877757A
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- control system
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- 238000001514 detection method Methods 0.000 title claims abstract description 17
- 230000003321 amplification Effects 0.000 claims abstract description 23
- 238000003199 nucleic acid amplification method Methods 0.000 claims abstract description 23
- 238000012360 testing method Methods 0.000 claims abstract description 10
- 238000001914 filtration Methods 0.000 claims abstract description 7
- 238000000034 method Methods 0.000 claims description 9
- 230000005611 electricity Effects 0.000 claims description 6
- 230000010349 pulsation Effects 0.000 claims description 6
- 230000000694 effects Effects 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000011897 real-time detection Methods 0.000 description 2
- 210000001367 artery Anatomy 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 210000003462 vein Anatomy 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P7/00—Arrangements for regulating or controlling the speed or torque of electric DC motors
- H02P7/06—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual DC dynamo-electric motor by varying field or armature current
- H02P7/18—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual DC dynamo-electric motor by varying field or armature current by master control with auxiliary power
- H02P7/24—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual DC dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices
- H02P7/28—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual DC dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices
- H02P7/285—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual DC dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices controlling armature supply only
- H02P7/29—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual DC dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices controlling armature supply only using pulse modulation
- H02P7/2913—Arrangements for regulating or controlling the speed or torque of electric DC motors for regulating or controlling an individual DC dynamo-electric motor by varying field or armature current by master control with auxiliary power using discharge tubes or semiconductor devices using semiconductor devices controlling armature supply only using pulse modulation whereby the speed is regulated by measuring the motor speed and comparing it with a given physical value
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Direct Current Motors (AREA)
Abstract
The invention provides a kind of DC motor speed-regulating control system, including：Brushed DC motor, is arranged on wheelchair；Power supply, powers to brushed DC motor；Current-to-voltage convertor, is connected with brushed DC motor, and the pulsating current for will flow through brushed DC motor is converted into pulsating volage；Filter amplification circuit, is connected with current-to-voltage convertor, for being filtered to pulsating volage and amplifies；Reshaper, and filter amplification circuit, for by after filtering and the pulsating volage that amplifies carries out being shaped to square wave；Microprocessor, with unit and the speed adjustment unit of testing the speed, the unit that tests the speed is connected with reshaper, and ripple frequency is obtained for catching square wave, calculates the rotating speed of brushed DC motor according to pre-defined rule based on the ripple frequency；Speed adjustment unit is connected with brushed DC motor, for adjusting the rotating speed of brushed DC motor and then adjusting the travel speed of wheelchair.Present invention also offers a kind of speed detection method used in above-mentioned DC motor speed-regulating control system.
Description
Technical field
The present invention relates to a kind of DC motor speed-regulating control system and its speed detection method.
Background technology
In DC motor speed-regulating control system, the general nature static that system is improved using the method for speed closed loop control
Energy and dynamic property.The premise of speed closed loop is the detection of speed, and the method for current detection speed is mainly using centrifugal turn
Fast table, stroboscope, photoelectric figure revolution counter etc. are realized.
Centrifugal tachometer is mainly sedimentator, speed changer and indicates the part such as scale to constitute, wherein the big portion of sedimentator
Divide and use with heavy hammer structure.During velocity measuring, not only weight is easily jolted by ground and is influenceed, and causes
There is certain error in the speed of detection；And indicate the uneven display for also resulting in speed of scale of scale inaccurate with reading；
When stroboscope is according to the flashing rate of instrument and the equal rotational frequency of measured object, flashing rate is turning for measured object
Speed, but when the light source of instrument is blocked, the precision for testing the speed can be influenceed；Photoelectric figure revolution counter is using Electrophotosensitive unit
Part, measures and shows the instrument of rotating speed.But when bad weather, the work accuracy of photoelectric sensor can be influenceed, cause
The error of velocity measuring.
In addition, these detection means are required for being fixed on special position greatly, belong to extra on wheelchair
Speed detector, which not only adds production cost, and increases the complex degree of structure of wheelchair, to user with
Burden is carried out.
The content of the invention
The present invention is carried out to solve the above problems, it is therefore intended that provide DC motor speed-regulating control system and its
Speed detection method.
The invention provides a kind of DC motor speed-regulating control system, have the feature that, including：Brushed DC electricity
Machine, is arranged on wheelchair, for driving wheelchair；Power supply, is powered to brushed DC motor；Current-voltage converter, and has
Brushless motor is connected, and the pulsating current for will flow through brushed DC motor is converted into pulsating volage；Filter amplification circuit, with
Current-voltage converter is connected, and for being filtered to pulsating volage and is amplified；Reshaper, and filter amplification circuit, for will
After filtering and amplify pulsating volage carry out being shaped to square wave；Microprocessor, with unit and the speed adjustment unit of testing the speed, tests the speed
Unit is connected with reshaper, and ripple frequency is obtained for catching square wave, and being calculated according to pre-defined rule based on the ripple frequency has brush
The rotating speed of direct current generator；Speed adjustment unit is connected with brushed DC motor, rotating speed and then regulation for adjusting brushed DC motor
The travel speed of wheelchair.
The invention provides a kind of DC motor speed-regulating control system, can also have the feature that, including：Wherein,
Current-voltage converter is any one in resistance, current transformer and Hall element.
The invention provides a kind of DC motor speed-regulating control system, can also have the feature that, including：Wherein,
Pre-defined rule is：Wherein, fn is the ripple frequency of electric current, and n is the rotating speed of brushed DC motor, and k is brushed DC
The number of segment of motor, p is the magnetic pole logarithm of brushed DC motor, and c is the coefficient relevant with the parity of number of segment k, and k is
C=1 during even number, k are c=2 for odd number.
Present invention also offers the speed detection method in above-mentioned DC motor speed-regulating control system, with such spy
Levy, including：The pulsating current that will flow through brushed DC motor using current-voltage converter is converted into pulsating volage；Using filter
Ripple amplifying circuit is filtered to pulsating volage and processes and amplify；It is electric to the pulsation for processing after filtering and amplifying using reshaper
Repoussage forms square wave；Square wave is caught using microprocessor, obtains ripple frequency；And the arteries and veins is based on using microprocessor
Dynamic frequency is calculated the rotating speed of brushed DC motor according to pre-defined rule.
The effect of invention and effect
According to DC motor speed-regulating control system involved in the present invention and its speed detection method, because in direct current generator
Current-voltage converter, filter amplification circuit and microprocessor are provided with speed-adjusting and control system, brushed DC electricity is extracted
The ripple frequency of machine, you can the rotating speed of real-time detection wheelchair, and it is adjusted, so, DC motor speed-regulating of the invention
Control system, not only reduces the production cost of wheelchair, reduces the complexity of wheelchair, and direct current generator of the invention is adjusted
The detection speed method of speed control system is provided on the circuit in microprocessor speed-adjusting and control system, and so setting will not be because
Cause the deviation of velocity measuring for the influence of vibrated, road conditions or weather, wheelchair can be accurately detected in real time
The rotating speed of running motor, improves the accuracy of velocity measuring.
Brief description of the drawings
Fig. 1 is the structural representation of DC motor speed-regulating control system in embodiments of the invention；
Fig. 2 is the circuit diagram of filter amplification circuit and reshaper in embodiments of the invention.
Specific embodiment
In order that technological means, creation characteristic, reached purpose and effect that the present invention is realized are easy to understand, it is real below
DC motor speed-regulating control system and its speed detection method based on wheelchair are specifically addressed to the present invention to apply example combination accompanying drawing.
Fig. 1 is the structural representation of DC motor speed-regulating control system in embodiments of the invention.
As shown in figure 1, DC motor speed-regulating control system 100 includes power supply 10, brushed DC motor 20, current-voltage
Converter 30, filter amplification circuit 40, reshaper 50 and microprocessor 60.
Power supply 10 is used to be powered to brushed DC motor 20.
Brushed DC motor 20 includes brush and commutator, and DC voltage is introduced commutator by power supply 10 by brush,
Impressed DC voltage and DC current are converted into exchange potential and handed over by commutator in the rotary course of brushed DC motor 20
Stream electric current, produces pulsating current in current supply circuit.
Current-voltage converter 30 is connected with commutator, for gathering pulsating current, pulsating current is converted into pulsation electricity
Pressure.Current-voltage converter 30 is any one in resistance, current transformer and Hall element.In the present embodiment, electricity
Stream-electric pressure converter 30 uses current transformer.
Fig. 2 is the circuit diagram of filter amplification circuit and reshaper in embodiments of the invention.
As shown in Fig. 2 filter amplification circuit 40 is connected with current-voltage converter 30, for being filtered to pulsating volage
Ripple is processed and amplified.Filter amplification circuit 40 includes the first filter and amplification unit 41 and the second filter and amplification unit 42.
First filter and amplification unit 41 by electric capacity C5, resistance R10, the first operational amplifier, resistance R8, feedback resistance R2,
Resistance R12 and electric capacity C7 is constituted.One end of electric capacity C5 is connected with current transformer, another terminating resistor R10, resistance R10's
The input anode of the first operational amplifier of another termination, input cathode the connecting resistance R8, resistance R8 of the first operational amplifier
The other end ground connection.The output end of the first operational amplifier meets feedback resistance R2, the computing of another termination first of feedback resistance R2
The input cathode of amplifier.Wherein, one end of resistance R12 is connected to the same side of electric capacity C5, other end ground connection with resistance R10.
Electric capacity C7 mono- terminates the input anode of the first operational amplifier, other end ground connection.In the present embodiment, resistance R8 and feedback
The resistance of resistance R2 is chosen and is followedRelation, wherein, AVIt is multiplication factor, in actual applications, can basis
The amplification demand of user is adjusted to the resistance of R2 and R8.
Second filter and amplification unit 42 is by electric capacity C4, resistance R9, the second operational amplifier, resistance R7, feedback resistance R1, electricity
Resistance R11 and electric capacity C6 compositions.One end of electric capacity C4 is connected with the output end of the first operational amplifier, another terminating resistor R9,
The input anode of the operational amplifier of another termination second of resistance R9, the input cathode connecting resistance of the second operational amplifier
The other end ground connection of R7, resistance R7.The output end of the second operational amplifier meets feedback resistance R1, another termination of feedback resistance R1
The input cathode of the second operational amplifier.Wherein, one end of resistance R11 is connected to the same side of electric capacity C4 with resistance R9, another
End ground connection.Electric capacity C6 mono- terminates the input anode of the second operational amplifier, other end ground connection.In the present embodiment, resistance R7
And the resistance of feedback resistance R1 is chosen and is followedRelation, wherein, AVIt is multiplication factor, in actual applications,
The resistance of R1 and R7 can be adjusted according to the amplification demand of user.
Reshaper 50 and filter amplification circuit 40, are shaped to for the pulsating volage through processing after filtering and amplify
Square wave.Reshaper is a phase inverter, and one end of phase inverter is connected with the output end of the second operational amplifier, the other end and Wei Chu
Reason device 60 is connected.In the present embodiment, the amplitude of the square wave that pulsating volage is shaped to is 3.3V.
Microprocessor 60 has test the speed unit 61 and speed adjustment unit 62.
The unit 61 that tests the speed is pulse capture section, is connected with phase inverter, for catching pulsation that square wave obtains pulsating current frequently
Rate.The rotating speed of brushed DC motor 20 is calculated according to pre-defined rule based on the ripple frequency.
Pre-defined rule is：
Wherein, fnIt is the ripple frequency of electric current, n is the rotating speed of brushed DC motor, and k is the commutator segment of brushed DC motor
Number, p is the magnetic pole logarithm of brushed DC motor, and c is the coefficient relevant with the parity of number of segment k, c=1, k when k is even number
For odd number is c=2.
Speed adjustment unit 62 is connected with brushed DC motor 20, the rotating speed for adjusting brushed DC motor 20.
The speed detection method of DC motor speed-regulating control system 100 is comprised the following steps：
Step one, power supply 10 carries out rotary work under driving brushed DC motor 20, and power supply 10 passes through brush by direct current
Pressure introduces commutator.
Be converted into for impressed DC voltage and DC current to exchange potential and alternating current by step 2, commutator, is supplying
Pulsating current is produced in electrical circuit.
Step 3, the pulsating current of brushed DC motor 20 is flowed through using current transformer collection, and pulsating current is changed
Pulsation.
Step 4, is filtered to pulsating volage using filter amplification circuit and processes and amplify.
Step 5, it is 3.3V's to use pulsating volage of the phase inverter to processing after filtering and amplifying to carry out being shaped to amplitude
Square wave.
Step 7, is caught using the unit 61 that tests the speed of microprocessor 60 to square wave, obtains the pulsation of pulsating current frequently
Rate；Based on ripple frequency according toIt is calculated the rotating speed of brushed DC motor 20.
The effect of embodiment and effect
DC motor speed-regulating control system and its speed detection method in embodiment, because in DC motor speed-regulating
Current-voltage converter, filter amplification circuit and microprocessor are provided with control system, brushed DC motor is extracted
Ripple frequency, you can the rotating speed of real-time detection wheelchair, and it is adjusted, so, DC motor speed-regulating control of the invention
System, not only reduces the production cost of wheelchair, reduces the complexity of wheelchair, and DC motor speed-regulating control of the invention
The detection speed method of system processed is provided on the circuit in microprocessor speed-adjusting and control system, and so setting will not be because of receiving
Cause the deviation of velocity measuring to the influence of vibration, road conditions or weather, the traveling of wheelchair can be accurately detected in real time
The rotating speed of motor, improves the accuracy of velocity measuring.
In addition, the collection converter in DC motor speed-regulating control system in the present embodiment uses Current Mutual Inductance
Device.Because the simple structure of current transformer, the pressure drop to dc source has little to no effect, voltage signal is not resulted in
Deviation caused by transfer process, improves the accuracy of the velocity measuring of DC motor speed-regulating control system.
Above-mentioned implementation method is preferred case of the invention, is not intended to limit protection scope of the present invention.
Claims (4)
1. a kind of DC motor speed-regulating control system, for the travel speed of real-time regulation wheelchair, it is characterised in that including：
Brushed DC motor, is arranged on the wheelchair, for driving the wheelchair；
Power supply, is powered to the brushed DC motor；
Current-voltage converter, is connected with the brushed DC motor, the pulsation electricity for will flow through the brushed DC motor
Circulation changes pulsating volage into；
Filter amplification circuit, is connected with the current-voltage converter, for the pulsating volage to be filtered and amplified；
Reshaper, and the filter amplification circuit, for by after filtering and the pulsating volage that amplifies carries out the side of being shaped to
Ripple；
Microprocessor, with unit and the speed adjustment unit of testing the speed, the unit that tests the speed is connected with the reshaper, for catching
State square wave and obtain ripple frequency, calculate the rotating speed of the brushed DC motor according to pre-defined rule based on the ripple frequency；It is described
Speed adjustment unit is connected with the brushed DC motor, for adjusting the rotating speed of the brushed DC motor and then adjusting the wheelchair
Travel speed.
2. DC motor speed-regulating control system according to claim 1, it is characterised in that：
Wherein, the current-voltage converter is any one in resistance, current transformer and Hall element.
3. DC motor speed-regulating control system according to claim 1, it is characterised in that：
Wherein, the pre-defined rule is：
Here, fnIt is the ripple frequency of electric current, n is the rotating speed of brushed DC motor, and k is the number of segment of brushed DC motor, p
It is the magnetic pole logarithm of brushed DC motor, c is the coefficient relevant with the parity of number of segment k, c=1 when k is even number, and k is strange
Number is c=2.
4. a kind of speed detection method in the DC motor speed-regulating control system described in claim 1, it is characterised in that：
The pulsating current that will flow through the brushed DC motor using current-voltage converter is converted into pulsating volage；
The pulsating volage is filtered using filter amplification circuit is processed and is amplified；
Square wave is shaped to the pulsating volage by the filtering process and amplification using reshaper；
The square wave is caught using microprocessor, obtains ripple frequency；And
The rotating speed that the ripple frequency is calculated the brushed DC motor according to pre-defined rule is based on using the microprocessor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710152263.8A CN106877757A (en) | 2017-03-15 | 2017-03-15 | DC motor speed-regulating control system and its speed detection method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201710152263.8A CN106877757A (en) | 2017-03-15 | 2017-03-15 | DC motor speed-regulating control system and its speed detection method |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109861598A (en) * | 2017-11-30 | 2019-06-07 | 大陆汽车电子(芜湖)有限公司 | System and method for detecting the revolving speed of brushed DC motor |
| CN110988381A (en) * | 2019-12-19 | 2020-04-10 | 东莞市深鹏电子有限公司 | Method and device for detecting rotating speed of direct current motor |
| CN111830275A (en) * | 2019-04-18 | 2020-10-27 | 现代摩比斯株式会社 | Apparatus and method for estimating motor rotation speed in electronic brake system |
| CN112255427A (en) * | 2019-07-22 | 2021-01-22 | 宁波拓邦智能控制有限公司 | Motor rotating speed detection method and device |
| CN112595971A (en) * | 2020-10-15 | 2021-04-02 | 浙江仕优驱动科技有限公司 | Locked rotor detection method and controller of direct current brush motor based on FFT technology |
| CN114610087A (en) * | 2022-03-09 | 2022-06-10 | 陕西理工大学 | A DC motor speed measurement and control circuit |
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| CN101408585A (en) * | 2008-08-29 | 2009-04-15 | 上海第二工业大学 | Method for testing evenness of bush DC motor windings |
| CN101908854A (en) * | 2010-08-24 | 2010-12-08 | 南京新乐能电子科技有限公司 | DC motor speed-regulating controller |
| CN105680744A (en) * | 2016-03-08 | 2016-06-15 | 江苏仁源电气有限公司 | Speed regulation device and speed regulation method of DC brush motor |
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2017
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| CN101408585A (en) * | 2008-08-29 | 2009-04-15 | 上海第二工业大学 | Method for testing evenness of bush DC motor windings |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109861598A (en) * | 2017-11-30 | 2019-06-07 | 大陆汽车电子(芜湖)有限公司 | System and method for detecting the revolving speed of brushed DC motor |
| CN109861598B (en) * | 2017-11-30 | 2020-12-04 | 纬湃汽车电子(芜湖)有限公司 | System and method for detecting rotation speed of brushed direct current motor |
| CN111830275A (en) * | 2019-04-18 | 2020-10-27 | 现代摩比斯株式会社 | Apparatus and method for estimating motor rotation speed in electronic brake system |
| CN111830275B (en) * | 2019-04-18 | 2022-05-10 | 现代摩比斯株式会社 | Apparatus and method for estimating motor rotation speed in electronic brake system |
| CN112255427A (en) * | 2019-07-22 | 2021-01-22 | 宁波拓邦智能控制有限公司 | Motor rotating speed detection method and device |
| CN110988381A (en) * | 2019-12-19 | 2020-04-10 | 东莞市深鹏电子有限公司 | Method and device for detecting rotating speed of direct current motor |
| CN110988381B (en) * | 2019-12-19 | 2022-03-08 | 东莞市深鹏电子有限公司 | Method and device for detecting rotating speed of direct current motor |
| CN112595971A (en) * | 2020-10-15 | 2021-04-02 | 浙江仕优驱动科技有限公司 | Locked rotor detection method and controller of direct current brush motor based on FFT technology |
| CN114610087A (en) * | 2022-03-09 | 2022-06-10 | 陕西理工大学 | A DC motor speed measurement and control circuit |
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